Herstellung von Formkörpern mit definierter Porenstruktur

Abstract

Fabrication of pellets with defined pore‐size distribution. The fabrication of porous alumina‐pellets of high mechanical strength and with a well defined pore‐size distribution by pelletization and by extrusion is described. Macropores can be introduced through solid material which is vaporized after agglomeration; the content of macropores can thereby be chosen within a rather wide range. The amount of micropores in the pellets can be controlled by thermal treatment (sintering). Mechanical strength is obtained if the primary particles are connected by bridges of solid material, generated from substances dissolved in the liquid which fills the pores before drying. The mechanism and the procedure leading to the formation of porous alumina‐pellets are also applicable if silica or zeolites are to be agglomerated into porous pellets of high mechanical strength.

Mesoporous Silica Applications

“…Moreover, the formation of porosity in two or three different length scales in an ordered fashion with interconnectivity between the pores and with hierarchical structure would be advantageous for a variety of applications because the reactant molecules need to access readily inside of the pore structure. Commercial support pellets are usually prepared by compacting fine micro-or mesoporous particles [117] Macropores are formed between the agglomerated particles. These macropores allow a fast mass transfer to the surface of the primary particles.…”